Diamond polishing and grinding device



I- 1945- E. ROTHAUSE R 8 ,099

DIAMOND POLISHING AND GRINDING DEVICE Filed May 1. 1942 2 Sheet-Sheet 1 I N VEN TOR.

0 m: flaw/105m.

1945' E. ROTHAUSER DIAMOND POLISHING AND GRINDING DEVICE 2 Sheets-Sheet 2 Filed May 1, 1942 a W WW M V 4// 0 0 F.

another.

Patented Aug. 14, 1945 I O ICE 7 DIAMOND POLISHING AND GRINDING r l .ln

,Eugeneltothauser, New York, N. Application Mayl, 1942, Serial Hog 141,259 .4.Claims. 51-229) This invention relates .to grinding and polishmg devices for gems', particularly diamonds and has for its main object to provide a device'of this character. which will be more practical andmore efficient than the devices now used 'for suclij purpose t Another object of my invention is to provide a device as characterized hereinbefore, which will be adaptedto mechanically andautomatically provide for three objects'in grinding a gem, namely: to adjust and fix in each of the following threematters; to find and fixthebestfpossible positions as to the grain of the gem "with reference to the grinding and polishing lapj'to adjust and fix the exact desired angle of the facet to be ground with reference to the axis of the gem, and to adjust to and fix the exact desired angle of the facets with reierence to one Still a further object of my invention is to provide a device of the above novel and desirable qualities which may be controlled by the operator by hand and'may be moved to various positions on the lap as necessary and as usual withgem grinding and polishing, wherein the gem may easily be observed by him at any time, and which still will maintain the three mentioned adjustments of the gem automatically, continuously and in their respective fixed positions during all the operations, changes and observations.

Other objects of my invention will be apparent as the specification of the same proceeds,"and among others I may mention: to provide a gem grinding and polishing device ofthe novel desirable qualities indicated which nevertheless will be simple in construction, inexpensive to manufacture, and easily adapted to be employed and used in present gem and diamond grinding and P lishing establishments with practically no change in them.

In the drawings forming a part of this specifi- I cation and accompanying the same: 7

Fig. 1 is a side elevational'view of my novel gem grinding and polishing device, portions of the lap and of the working table or, bench only" being shown;

Fig. 2 is a plan view of the device shown in Fig. 1;

Fig. 3 is a fragmentary sectional .elevation on a larger scale, thesection being taken on the line 3-4 of Fig. 2, and

Fig. 4is a bottom view of a gem holder chuck being a portion ofmy device;

Fig. -5.is another fragmentary sectional elevation, the sectionbeing taken on the line 5-5 .of

In grinding and polishing a diamond or other I em,'it is veryimportant to set the axis of said gem exactly perpendicular-"to the surface'of the grinding or polishing lap. 'It is also'very important to be able't'o tilt the gem exactly to the angle which the 'iacet to be ground will have with said" vertical axis. l-ls'opwhen doing the grinding operations, thebest relation of thegrain of the gem tothe grinding and polishing lap must be found for best results; as it is well known-in this art, and, finally, aiter afacet has been ground or polished; the gem isto be rotated around its axis to the exact angle desired between the facet "just finished andthe next one to be ground.

Most "of these "adjustments have. :been .done heretofore by hand'an'dlby thejudgment of the expert diamond grinder and polisher, and the gem to be groundwas'held inthe desired established position by hand. :It is obvious that this method is very inferior, it is slow, uncertain anddifiicult,

and th result depends on the skill and careful adaptation; patience and perseverance of the operator, and even with the-best-expertknowledge "and best'attention, very often mistakes will happen and the'gem may be. impaired, causingigreat financial loss.

'I am aware of the fact that devices and machines have been proposed whereby these adjustmentsmay be done mechanically and automatically, but, to my knowledge, none of these devices were practicaland none of .them are. in use today, so that gem and diamond grinding still is done by manual labor'and these adjustments and settings are made by'relying on the knowledge and skill of the operator.

. With my invention, a device 7 is provided whereby the best position of the gem with reference tothe adjustment of the grain to the grindin'g lap may befoundand fixed or set. Also,ythe

exact angle of a facet to the axis of the gem, and,

finally, the exactldesired angles of the-facets to oneganother. All this with very simple means and operations and the gem may be fixed in my device inithe exact desired position and so kept during the grinding operations, While my Idevice also may be'controlled by .hand by the operator and may be removed and observed at any time, as it will be necessary tOthe' best grinding results duringsuch operations,without disturbing the mentioned three settin s jthereof, and with the ability to easily and safely return the same into .its..0per.atiye position and resume the grinding without any. new settin Wit-hthe above objects. in view, my invention mainly consists of an arm which is easily slidover a portion of which is arranged the rotating grinding or polishing lap A metal base plate |2 may be set into the working bench or table in front of the lap H, and a metal block |3 may be arranged over said plate l2 'slidable thereon in an inward or outward radial direction with reference to the lap II, as indicated by the double arrows i4. An arm I5 is secured over the block l3, as by the screws l6, andmy adjusting device proper, indicated, in general, by

the numeral I1 is housed in and carried by an outer ring l8 permanently secured to the outer end l9 of the arm l5 as by the screws 29. An inner ring 2| is closely, but slidably, set within the ring l8, being held inposition by several pairs of upper and lower plates 22 and 23 secured at the upper and lower surfaces, respectively, of

the inner ring 2| at the desired places thereof,

as by the screws 24, and having respective projecting portions 25 and 26 slidably engaging the upper and. lower surfaces of the outer ring I8.

, It will be seen that the inner ring 2| may slide in a right handed or left handed direction and rotate within the outer ring H! to any desired position, the projections 25 and, 26 ofthe plates 22 and 23 riding on the upper and lower respective surfaces of the outer ring 3. A set screw 21 may be provided through the outer ring l8 at any appropriate portion thereof, engaging the inner ring 2 I, and said inner ring may be secured in any of its positions within said .outer ring by the set screw 21, as it will be obvious.

The gem to be ground is indicated. at'28 and may be set into a holder forithe same, as shown at 29, which, again, may: be clamped and secured in the chuck (Fig. 3), said chuck having a rectangular recess or opening 3| into which said gem holder 29 will fit, said chuck alsohaving four axial incisions or separations 32,.whereby it will havefour arms or branches 33, slightly separated from one another bysaid 'incisionsor slots 32, but being adapted to be brought nearer to one another or closed upon one another by their resiliency when an inward force is exerted on their conical outer surfaces 34. The gem holder 29 may simply be formed by a metal bar having a square upper portion to fit into the opening in the chuck, the lower end thereof having a recess into which is firmly set, projecting therefrom, the gem 28, prepared by sawing,

preliminary trimming, grinding etc., for such a setting.

In my device, this chuck may have a screw threaded upper portion set into a tube 36 and movable inwardly or outwardly in said tube by rotating the same and by the action of the screw threads 31 within said tube. -A knurled knob 38 may be provided at the upper end of the tube 36 to facilitate its rotation in a right handed or left handeddirection according whether the chuck 3D is' tobe moved inwardly or outwardly of the tube 35;

Tube 36 is snugly but slidably set into a tube or sleeve 39, said tube having a conical inner lower termination 49, which cone may cooperate with the outer cone surface 34 of the chuck 30. When the chuck 30 is lowered in the tube or sleeve 39 by the respective rotation of the inner tube 36, the cone surface 49 will cease its pressure on the surface 34 and the chuck may open, while when the chuck is pulled inwardly into the sleeve 39 by the opposite rotation of the inner tube 36, the said two cones will cooperate and the branches 33 of the chuck 30 will be pressed closer to one another, thereby firmly securing the gem holder 29 and with it the gem 28 in said chuck and in my device. A pin 39a secured into the tube 39 may project into a vertical slot 30a in the chuck 3i], and may slide therein so as to prevent a rotation of the chuck when it is moved inwardly or outwardly.

The sleeve or tube 39, finally, is set, also snugly but slidably, in an outer sleeve 4|, the upper portion 42 of said intermediate sleeve or tube 39 projecting over the top of the-outer sleeve 4|, and a knurled knob 43 witha dial disc 44 is secured on said upper, portion 42 of the tube 39, as by the screws 44a. v

It will be seen that the intermediate tube 39, and the dial 44 with it, may be rotated within the outer sleeve 4|, and to secure the respective positions of the two sleeves within one another without impairing their relative rotation, a channel 45 may be cut in the intermediate sleeve 39, and a pin 46 may be secured inwardly in the outer sleeve 4|, said pin riding in said channel 45, as will be obvious. I

Two oppositely projecting but: axially aligned shafts 41 and 48 may be secured on the sleeye 4|, as by their rectangular terminations49, and may be journaled, by their outer ends 59,-in the inner ring 2|, so that the whole central gem holding device proper, withits various sleeves and tubes, all may berotated in a horizontal direction by the right handed or left handed sliding or rotation of the inner ring 2|, within the outer ring l8, and said gemholding and adjusting tubes and sleeves with their associated parts may also swing in a vertical plane on the horizontal axis of the shafts 41 and 48 by rotating said shafts, through their journaled portions 50, in the inner ring 2|. 3

Formeasuring the said swinging of my device in a vertical planev on the shafts 41 and'48and for fixing the samein any desired position, a

vertical dialplate 5| may be secured on the inner ring 2| at any desired appropriate portion thereof, as by ,an angular lower base 52 thereof, the same being secured on the upper surface of the respective portion of the inner ringf 2|'by the screws 53. i J i The upperend 54 of the verticaldialplate. 5| is in the form of a section or an'arc' of acircle and has the teeth 55 therein with right handed and left handedmarkings starting at; a central zero and indicating angles in a :right handed and left handed direction from said central up to 45 or in eachdirection.

A standard or post 56 may be secured into'the shaft 41 to the rear'of the dial plate 5|Tand may have a forward upperangular"projection 51 through which passes the securing s'crew58, the lower pointed end 59 of which may enter any of the teeth in the dialplate' 5|; 1. i

The devices associated with' the' vertioa'l dial plate 5| will serve to set the gem intosthe right angular position with reference to the vertical axis of the device,'as'willbem'ore fully explained e a te I For rotating the *gem o'n it's-axis and setting {the relative angles "of the 'facets to be ground thereon, I -employ the 'inentioned dial disc '44 and its associated parts, as also will be more fully explained presently.

An "angular member, generally indicated by the numeral 60 may be radially "secured on the outer sleeve 4|, as by the screw 61, (Figs. 1, 2 and The outer end 62 of said member "60 is over the rings I 8 and 2 l' and anadjusting screw '53 passes th'erthrough, the inner pointed end li l of which 'may'engage any of theteet'h 65*of the dial disc 44. I H

I may remark that I-preferto set said-member 60 and said securing and adjusting screw '63 at right-z m'g1e to the rocking shafts 41 andg4'8 of my device, while, of course, 'it 'may be*placed.

to be ground. This will be done b'y'withdrawing the screw 58 from the dial 5|, tilting the device on the shafts 41 and 4-8 and then securing it at the right angle by thescrew 58 as will be ob- 'vio'us.

Now my device is lifted off the platelZ, the gem 28 placed into the gem holder 29; asindicated, whereupon the gem holder!!! will be placed into the opening of the chuck 39, the inner tube 36 rotated by the knurled knob 38 in such a manner as to draw the chuck 30 inwardly and the conical surfaces lfl'will press on the conical surfaces 34 of the chuck, and thereby firmly close the chuck on the gem holder 29. The device will now be replaced on the plate l2 and adjusted until the gem 28 will rest on the upper grinding surface 61 of the lap ll.

Now I start a preliminary trial grinding operation to find out whether the grain of the gem is in a right relation to the lap II which an expert in this art may judge upon trial. When the result is not satisfactory, the set screw 21 will be loosened, thereby permitting a circular swinging of the inner ring 21 in the outer ring 18, and the inner ring will be placed into various positions, thereby changing the position of the facet with reference to the lap II, until the best grinding position with relation to the grain of the gem 28 is obtained, whereupon the screw 21 will be driven tight against the inner ring 2| securing the same, and thereby the whole operating mechanism, and the gem secured therein, in that position.

The grinding and polishing operation on the facet now exposed to the upper surface 51 of the lap ll may be executed, and as usual, the operator may move the block 13 radially inwardly and outwardly, thereby changing the position of the gem 28 on the lap H, as desired, and as he judges best. For this purpose, a limiting and guiding post 68 may be arranged on the one side of the arm l5, while the block I3 may have a rearward extension rod 69 which is engaged by another post or pin 10 on the other side of the sliding arm and block 13. This arrangement will permit an easy inward and outward sliding of the block l3, arm l5 and all my devices with the gem- -th rern attire i'nner end or he arifn -l'5-, and will prevent sieeway n'iitloh thereof, mam 't'ime to time the tpemtor-may-iiit the device Q's-the lap l l'anu inspect *the workdone.

A iter the'firstfacet, set as described abo've, is ground and polished to the extent desired and as --'judged 'bythe *expert grinder operating the arm 15 and watching the progre'ss 'o'f the- 011ieration; these'curing or setting screw '64 eooperating with-the dial disc 44 Will be withdrawn, thereby "permitting an axial rotation or thesa'id concentric central tubes with the gem holder and the gem therein, while their inclination to the'suiffa'ce 61 of the lap will remain 'fiiie'd by thedial 5] and the screw 58 set'therei'nto. The said concentric central tubes with" the gem ther'ein will now'be rotated aroimdtheycentral axis thereof 'bythe 'knurled knob "43, which, as has been mentioned, is'integral with the dial disc -44-'an'd is secured "on thetu-b'e $19 by thefscrew's 44a, until the desired angle for the next facet to be ground is reached, whereupon thesetting and securing screw 6'3 will be turned in an inward direction to engage and fix the dial 44in that position. It will be obvious that the'next facet may now be ground in a similar manner as the first one, and that it will have the pro-determined angle with reference to the earlier one.

In this manner, facets all around the circumference of the gem'may be ground with perfection and with exactly the angles between them "as pre-determined for thebest *e'ffect for the gem.

Ashas been mentioned, it is to be noted that whilemy device permits a mechanicalflxedand absolutely exact and reliable setting of the angles of the facets with reference to thecentralaxis.

of the gem and the angles between the adjacent facets, and while it also permits a mechanicaI, absolutely'reliable and fixable settingfof the gem to the best direction of the grain for grinding and polishing, still the actual grinding and polishing is done by themanipulation of the arm l5 and block [3 by the grinder himself, so that he may exert his skill and guide the operation to the best effect by his personal touch, and it will be obvious that while my device is extremely simple, still it permits a perfectly reliable and absolute fixed setting of the gem for all the requirements mentioned hereinbefore, and at the same time it will permit a perfect guiding and supervising of the operation by the expert grinder himself, and an observation of the work done at any time and with greatest facility and with an easy, quick and safe restarting of the grinding or polishing.

I also want to remark that in the embodiment shown, the tilting of the central portion of my device with the gem carried by it, may be done only in the right handed direction, as viewed in Fig. 1, since in the other direction the fixing screw 63 for the setting of the angles between the facets would hit the rings I8 and 2| when the central tubular portion of the device is attempted to be tilted in a left handed direction. This, however, is no impairment in the working of my device, since all the angles desired may be set by a right handed swinging of the central tubular portions, as will be obvious.

- The farthest swinging necessary for grinding and polishing is about 45, and I show a vertical dial 5| with markings from zero to 45 in both directions. In a slightly modified embodiment of my device, said setting or fixing screw may be arranged further inwardly, or, vice versa, the

rings, I8 and 23 may bemadelarger, with respect to the rotatingdial 44 and the fixing or setting screw 63, so that the central tubular portion o fj said parts aids in the clearness of showing of the drawings, particularly of Fig, 1, but in such a position the knob 43 may hit the inner ring 2| before the central tubular part of my device is tilted to 45-50, and in actual practicesaid parts may be set lower, or the rings l8 and 21 made larger, as mentioned, permitting a limit tilting on the shafts 41 and 4 8 even over 50 ifthat should be desired in diamond grinding or insome other application and use of my device. 7 What I claim as new, is: v

1. In a gem grinding and polishing device, having a rotatable lap, an arm with meansat its end to'hold the gem to be ground and polished,

said, end projecting over said lap, said end of the-arm being in the form of a relatively stationary ring and another concentric ring rotatablyset into said stationary ring, three concentrio-tubes at the center of said rings telescopically, set into one another, and normally I perpendicular to the plane of said rings, two

transverse shafts secured on and oppositelyprojectingfrom the outermost of said, tubes, the outer ends of said shafts being journalled in said inner ring so that said tube may be set to a desired inclination to the plane of said ring, but

will rotate with said inner ring, the intermediaate tube being rotatable within said outer tube but being preventedfrom an axial'moving with 5.40

aeslaoas relation thereto, and the innermost. tube being axially movable within said intermediate tube, means between the intermediate and vinnermost tubes whereby the rotation of one willcause the other one to rotate therewith, means to rotate saidintermediate tube, means to axially move and thereby lower or raise, said innermost tube, said gem being secured in the lower end of said innermost tube.

I 2. In a device, as set forth in claim 1, said means to rotate said intermediate tube comprisinga disk shaped'knob at the upper end thereof, a toothed dial disk on said knob,.a member secured on said outermost tube, and a set screw in said member adapted to engage or disengage the teeth on said dial disk whereby to secure said intermediate tube and the parts associated therewith in the position into which they are rotated.

' 3. In a device, as setforth in claim 1, a. screw threaded-upward extension on said innermost tube, an upper tube set in said intermediate tube above said innermost tube, means to rotate said upper tube, the lower portion of said upper tube having inner screw threads engaging the screw threads on the. extension of said innermost tube, whereby upon the rotation of said upper tube said innermost tube will be raised or lowered within said intermediate tube.

V 4. In a device, as set forth in claim 1, an upstanding dial segment on said inner ring rotatable therewith, having a toothed circular are for its upper periphery, its center being set about opposite to one of said shaftson-said outer tube, an up-standing post secured on said shaft and swingable therewith,a set screw carried by the u'pper end of said post and adapted to engage or disengage the teeth of said dial segment and thereby secure said tubes in their tilted positions.

EUGENE RoTrmosnn. 

